Space heater



FIG. 1 is a top perspective view of a space heater, showing our new design;

FIG. 2 is a left side elevation thereof;

FIG. 3 is a rear elevation thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a front elevation thereof; and,

FIG. 7 is a right side elevation thereof. 

The ornamental design for a space heater, as shown. 